Apparatus for sealing pipe flanges

Abstract

An apparatus for sealing a pair of circularly coacting pipe flanges which includes a seal around the outer periphery of both the flanges for sealing the outer periphery and a bolt having a coacting nut extending through the bolt holes of the flange. A first sealing ferrule is positioned between the bolt head and one flange and a second sealing ferrule is positioned between the nut and the other flange. The ferrules include a conical exterior surface tapering inwardly and extending into the bolt holes for preventing the escape of fluid through the bolt holes. Each head and first ferrule and each nut and second ferrule include coacting tapered surfaces for pressing the ferrules into a sealing relationship with the bolt and flanges.

What is claimed is: 
     
       1. An apparatus for sealing a pair of circular coacting pipe flanges which are normally secured together by a plurality of bolts and nuts extending through bolt holes in the flanges comprising, sealing means connected to and extending around the outer periphery of both of said flanges for sealing the outer periphery of said flanges,   a bolt having threaded portions at each end and an unthreaded portion between the threaded portions, and having a coacting first and second nuts connected to the threaded portions, and extending through each of the bolt holes,   a first sealing ferrule positioned about each bolt between the first nut and the bolt hole and engaging the unthreaded portion of the bolt for sealing,   a second sealing ferrule positioned about each bolt between the second nut and the bolt hole for engaging the unthreaded portion of the bolt for sealing,   said ferrules including a conical exterior surface tapering inwardly and extending into the hole for preventing the escape of fluids through the bolt holes,   each first nut and first ferrule including coacting tapered surfaces for pressing the first ferrules into a sealing relationship with the first nut, bolt and adjacent flange,   each second nut and second ferrule incuding coacting tapered surfaces for pressing the second ferrules into a sealing relationship with the second nut, bolt and adjacent flange,   the coacting tapered surfaces between the first ferrules and the first nuts and the coacting tapered surfaces between the second ferrules and the second nuts taper outwardly from the bolts toward the flanges.